git reimport

2019-03-15 13:47:54 +04:00
commit 3b461f73de
489 changed files with 1631603 additions and 0 deletions
--- a/archive/2016.08/2016.08.04
+++ b/archive/2016.08/2016.08.04
@@ -0,0 +1,150 @@
+package chelper;
+
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.TreeSet;
+
+import io.InputReader;
+import io.OutputWriter;
+
+
+public class Sazanka2N {
+
+  public void solve(int testNumber, InputReader in, OutputWriter out) {
+    int n = in.nextInt();
+    StringBuilder[] strings = new StringBuilder[n];
+    for (int i = 0; i < n; i++) {
+      strings[i] = new StringBuilder(in.nextString());
+    }
+
+    List<StringBuilder> same = new ArrayList<>();
+    List<StringBuilder> notSame = new ArrayList<>();
+
+    for (int i = 0; i < n; i++) {
+      if (sameChars(strings[i])) {
+        same.add(strings[i]);
+      } else {
+        notSame.add(strings[i]);
+      }
+    }
+
+    for (int i = 0; i < notSame.size(); i++) {
+      char need = notSame.get(i).charAt(notSame.get(i).length() - 1);
+      for (int j = same.size() - 1; j >= 0; j--) {
+        if (same.get(j).charAt(0) == need) {
+          notSame.set(i, notSame.get(i).append(same.get(j)));
+          same.remove(j);
+        }
+      }
+    }
+
+
+    for (int i = 0; i < same.size(); i++) {
+      char need = same.get(i).charAt(0);
+      for (int j = notSame.size() - 1; j >= 0; j--) {
+        if (notSame.get(j).charAt(0) == need) {
+          same.set(i, same.get(i).append(notSame.get(j)));
+          notSame.remove(j);
+        }
+      }
+    }
+    ArrayList<StringBuilder> all = new ArrayList<>();
+    all.addAll(same);
+    all.addAll(notSame);
+
+    for (int i = 0; i < all.size(); i++) {
+      for (int j = 0; j < all.size(); j++) {
+        char need = all.get(i).charAt(all.get(i).length() - 1);
+        if (i == j) {
+          continue;
+        }
+        if (all.get(j).charAt(0) == need) {
+          all.set(i, all.get(i).append(all.get(j)));
+          all.remove(j);
+          j = 0;
+        }
+      }
+    }
+
+    if (all.size() > 1) {
+      if (isOkWords(all)) {
+        out.print("MANY");
+      } else {
+        out.print("IMPOSSIBLE");
+      }
+    } else if (isOkWord(all.get(0))) {
+      out.print(all.get(0));
+    } else {
+      out.print("IMPOSSIBLE");
+    }
+  }
+
+  private boolean sameChars(StringBuilder string) {
+    char need = string.charAt(0);
+    for (int i = 1; i < string.length(); i++) {
+      if (string.charAt(i) != need) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  boolean isOkWords(ArrayList<StringBuilder> strings) {
+    Set<Character> chars = new HashSet<>();
+    for (int i = 0; i < strings.size(); i++) {
+      if (isOkWord(strings.get(i))) {
+        Set<Character> c = charsInWord(strings.get(i));
+        int size1 = chars.size();
+        int size2 = c.size();
+        chars.addAll(c);
+        if (size1 + size2 != chars.size()) {
+          return false;
+        }
+      }
+    }
+    return true;
+  }
+
+  boolean isOkWord(StringBuilder stringBuilder) {
+    Set<Character> chars = new HashSet<>();
+    char prev = stringBuilder.charAt(0);
+    chars.add(prev);
+    for (int i = 1; i < stringBuilder.length(); i++) {
+      while (i < stringBuilder.length() && stringBuilder.charAt(i) == prev) {
+        i++;
+      }
+      if (i >= stringBuilder.length()) {
+        break;
+      }
+      if (!chars.contains(stringBuilder.charAt(i))) {
+        chars.add(stringBuilder.charAt(i));
+        prev = stringBuilder.charAt(i);
+      } else {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  Set<Character> charsInWord(StringBuilder stringBuilder) {
+    Set<Character> chars = new HashSet<>();
+    char prev = stringBuilder.charAt(0);
+    chars.add(prev);
+    for (int i = 1; i < stringBuilder.length(); i++) {
+      while (i < stringBuilder.length() && stringBuilder.charAt(i) == prev) {
+        i++;
+      }
+      if (i >= stringBuilder.length()) {
+        break;
+      }
+      if (!chars.contains(stringBuilder.charAt(i))) {
+        chars.add(stringBuilder.charAt(i));
+      } else {
+        return new TreeSet<>();
+      }
+    }
+    return chars;
+  }
+}